Multicolor spray gun



April 18, 1950 A. H. DowNs uUL'rIcoLoR SPRAY GUN 2 Sheets-Sheet 1 Filed Oct. 10, 1944 N s Lk IN V EN TOR.

4a: 77 @wr/vf. BY

Patented Apr. i8, 1950 MUL'rlcoLoa SPRAY GUN Austin H. Downs, Glen Ridge, N. J., assigner to Eclipse Air Brush Co., Newark, N. J., a corporation of New J ersey Application october 1o, 1944, sensi No. 557,955

-4 claims.' (onzen-14o) This invention relates to novel spray devices for spraying materials. such as paints and the like. More particularly the invention is directed to novel spray guns for simultaneously spraying different colored surfacing or coating media such as paints and the like onto a surface.

According to this invention, a plurality of different colored coating media, preferably in the liquid form, such as paints and the like, are fed into a common fluid receiving chamber terminating in a discharge orifice. Said liquids are fed into said chamber at different places and preferably along the length or longitudinal axis of said chamber, which is preferably elongated. These liquids are preferably fed into the space of said chamber as streams or free columns. The viscosity and color of the liquid of one of said streams or columns differs from the corresponding characteristics of the liquid of another of said columns. The inlet or places of entry of saidv columns are preferably spaced from each other; and said columns as they enter said chamber are disposed at an appreciable angle and preferably at approximately right angles to the longitudinal axis of the receiving chamber. The liquid of greater viscosity is fed to said chamber at a place closer to said orice than the place of entry of said liquid of lower viscosity. The different colored, and preferably different viscosity liquids, are discharged from said orifice and as they leave this orifice in the course of their travel towards the surface to be coated a gaseous m'edium, such as air or the like atomizes said discharge and mixes said particles of discharge prior to their reaching the surfaces to be coated. vThe shape of the spray may be controlled by a pair of opposite streams of air projected towards each other and into the atomized discharge.

By employing my novel spray guns, I have obtained unusual and unique multicolored surface coatings by employing a single spraying operation. One of the outstanding characteristics of this invention is that by employing the invention multicolored coatings simulating hammered, pebbled, webbed, stipple or other type surfaces may be obtained by employing a single spraying operation.

Another object of this invention is to provide a novel spraying device.

Another object of this invention is to provide a novel spraying device for simultaneously spraying a mixture of different colored coating media onto the surface of an object to be coated.

These and other objects of this invention will be readily apparent from the following description and accompanying drawings. wherein:

Figure I represents a vertical longitudinal cross sectional view of a spraying device embodying the invention.

Figure II is a horizontal longitudinal cross sectional view taken along line lI-II of Figure I in the direction .of the arrows.

Figure III is a view in front elevation of the liquid throttling means shown in Figures I and II but modified to show a modification of the liquid line throttling means shown in Figs. I and Figure IV is a cross sectional view taken o n line IV-IV of Figure III and in the direction of the arrows.

Figure V is a cross sectional view of the nozzle shown in Figures I and II.

Figure VI is a cross sectional view of the fluid tip shown in Figures I and l1.

Referring to the drawings the numeral I3 designates the body of a paint spraying device illustrating an invention. The body I0 includes a barrel portion I I and a handle portion I2. The handle portion I2 extends downwardly from the barrel portion II and is inclined slightly to the rear thereof so that the body I0 has somewhat the appearance of an automatic revolver.

The lower end of the handle portion I2 has an internally threaded opening I3 therein. The opening I3 communicates with a passage I4 which exnds upwardly through the interior of the handle I2 to an air inlet valve chamber I5 in the rear part of the barrel portion of body I0. The chamber I'5 communicates -with an air distributing chamber I 6 disposed forwardly thereof in barrel portion Il. The chamber I6 is of smaller diameter than the chamber I5 and the shoulder at the end ofthe chamber I5 as it meets chamber I6 acts as a valve seat I1. A passageway I8 communicates with and extends from chamber I6 directly to a passageway I 9 extending along the barrel portion II from its rear towards the nozzle end of the device. Another passagewayjll communicates with and extends from chamber I6 directly to a valve chamber 2|.

Mounted in the valve chamber I5 is a suitable valve member 22 having a valve proper 23 adapted to engage the valve seat I1 and having an operating rod or stem 24 integral therewith and extending forwardly therefrom. The valve stem 24 extends through a suitable bearing opening 25 in the barrel portion and into an open inverted approximately V-shaped slot 26 in said barrel portion. The rear end of the valvemember 23 is provided with a stud or projection 21 receiving one end of a coiled compression spring 28. The other end of said spring 28 is positioned atomic in an exteriorly threaded socket 2l integral with and disposed at the forward end of a securing and tensioning adjusting nut 3l secured to the interiorly threaded rear end of the valve chamber I5. By this means the valve proper 23 is normally .held in tight engagement with the valve seat I1 sothat if air under pressure is admitted to the chamber I through the communicating' passageways. I3 and I4, no air under pressure is admitted through the passages I5, I8, I8, 25 and 2|.

The degree of force oi the valve 22 in the direction of the valve seat I1 is controlled by the compression spring 28 which in turn is controlled by the nut 85.

The valve chamber 23 is-provided with a valve seat 3I and communicates with and leads into a passageway 32 extending in the same 'direction as passageway I8 along the barrel interior and towards the nome end of the device. A needle valve 33 is mounted in the valve chamber 2i! through an internally threaded portion: of a mounting nut 34. The outer end of the valve 33 terminates in a knurled manipulating knob 35 by which the inner or valve end 31 may be adjusted relative to the valve seat 3i to regulate the flow of air into passage 32 as desired or to cut it off completely if required.

A trigger 38 has its upper end located at the apex of the slot 23 and is pivotally connected at its upper end to the barrel portion II by a pivot pin or bolt 38. 'Ihe trigger 38 extends below the slot 26 and its downwardly extending lower portion 40 is curved to provide a hand saddle so it may be readily and positively engaged by certain fingers of the hand of an operator. The rear face of that portion of the trigger 38 in the slot 25 has a rear bearing face 4i engaging the free front end of the valve stem 24. When the trigger 33 is swung rearwardly about the pivot 39, the valve stem 24 and valve proper 23 are forced rearwardly against the action of the spring 28 whereupon the valve 23 is moved away from the valve seat I1 to permit the admission of air under pressure from the chamber I5 into 1 eways I8, I8, I3, 28 and 2| and if the needle valve 33 is in open position,

1 strength normally to hold the valve 22 in closed position and the trigger in its fully extended open position shown in full lines in Figure I and tocause these parts to assume these positions when the external pressure on the trigger is suiilcientlyreduced. Thus a very simple and delicate control is provided forv controlling the admissionofairintothedeviceanditisvery easily regulated by an operator without 'the neceity of long training .and experience. For additional ease of manipulation and to insure a iirm grip. the'handle portion I2 is provided with a ringer lug or guard 42 projecting from said handle portion I2 directly below and adjacent the lower end of the trigger.

The barrel portion II, when the gun is .held in a normal position, extends ina horizontal direction forwardly from the handle portion I2 and is provided with a curved lug or hook 43 to provide a convenient hanging means for the device when not in use. On its upper part and in the vicinity ofthe midlength of the barrel portion, there is provided a cut out portion 44.

Thebarrelportion Ii isboredoentrally atits rear to provide a valve operating chamber 45 interconnecting with the slot 2l in barrel Il. Chamber 45 is internally threaded and has threadedly coupled thereto a hollow elongated nut 43 screwed into the rear end thereof. The nut 45 has a spring chamber 41 and a central opening 48 at its rear end and axially aligned therewith.

A valve rod .50, for controlling the supply of liquid material. extends into the valve operating chamber 45 through its front end and is movably mounted within a forward bearing part 5I of the central barrel bore. Inside said chamber 45 said rod is enlarged in diameter at 52 and is provided with two spaced shoulders 58 and 54. A vertical slot 55 is provided in the rod 50 between shoulders 53 and 54 and the upper portion of trigger 38 passes therethrough and is movable therein. The rear end of rod 50 is provided with an internally threaded bore 55 extending from said end through the rear end of slot 55. Threadedly engaged in said bore 55 is an operating rod 51 having a forward nose 58 projecting into said slot 55 and is adapted to be engaged by the trigger 38 when said trigger is moved rearwardly to operative position as hereinbefore described. Operating rod 51 may be of hexagonal or other polygon shape in section as at 59. A riveting collar is slidably borne to the rear end of rod 50. This collar 55 has a ilange 8| which engages the inner shoulder at the rear end of the nut 46. A rotatable knob 52 is xedly mounted on collar 60 so that rotation of knob 52 will rotate collar 50 and in turn the rod 51.

Intermediate its ends rod 51 is provided with a slide ring 54. A coil spring 55 is mounted around the front part of rod 51, with one end of said spring abutting against shoulder 54 and its other end against one face of ring 54. A coiled spring 56 is mounted around the rear part of rod 58, with one end engaging the opposite face of the ring 54 and its other end abutting against the nange 6i. These springs 65 and 6E normally urge the rod 51 and consequently valve rod 50 forwardly.

The adjustable positioning of the nose 58 through the knob 5I by the parts above described so that it is nearer to or further away from the trigger 38 permits a ilne variation of the relative movement of the valve rod 5I when the trigger is actuated. as well as a ilne control of the relative time of opening of the air valve 23 and the fluid outlet valve when the trigger is moved. The time may be thus controlled to eifect simultaneous operation of the air and iiuid outlet valves or later opening of the iiuid oiiet valve with respect to the air valve 23. In Figure I, the position of the nose 58 is such that the trigger 33 will iirst engage the stem 24 to nrst open valve 23 and then engages nose 58 to actuate valve rod 55.

The forward end of the barrel portion Il is provided with an internally threaded longitudinal bore forming a liquid receiving chamber 88. The lower part of the barrel portion II is enlarged at its underside to provide an extension 88 having a plm'ality of. and as shown merely for the purposes of illustration two, supply eways Il and 15 communicating with the supply chamber 3l. These eways 3l and 18 may be of the same or of different lengths and diameters and as iliustratively shown are of the same dimensions. Each of said eways is preferably disposed roughly at right angles to the chamber 53 and depends therefrom. The passageways 5I and19arepreferablyonebehindtheotherin single ille relationship and are roughly parallel to each other and are located in about the same plane. The passageways 99 and 19 may becylindrical and terminate at their lower ends in respectively enlarged internally threaded coupling bores 1| and 12 whose diameters are the same and materially greater than the diameter of passageways 99 and 19.

Demountably mounted in each coupling bore 1| and 12 is a double nipple 13 having each' of its ends 14 and 15 threaded. The hollow nipple 13 is internally threaded and has demountably mounted therein, an exteriorly threaded cylinder 19- having a central cylindricalbore or passageway` 11. The dimensions of theI bore or passageway 11 are preferably such that the length thereof is many times the diameter. In one of the preferred embodiments of the invention the length of passageway 11 is at least 5 times the diameter thereof. The diameter of the passageway 11 is much less than the diameter of passagewa'ys 99 and 19 and the length and diameter of the passageways 69 and 19 and the passageway 11 are so chosen that the fluid under pressure discharges substantially as a column from the passageway 11 through passageway 99 or 19 and into chamber 89 without to any great extent striking the sides of the passageway 59 or 19. While the passageways 11 may be of the same diameter, I prefer to employ cylinders 18 having passageways 11 of differentdiameters. Instead of employing the cylinders I6 in the demountable nipples 13, a lateral threaded opening 19 communicating with the opening 69 or 19 may be provided in the barrel portion II and in each of said openings 19 there may be provided a valve 99. 'I'he valve 99 extends into the passageway 99 or `19 and may be actuated by knob 8| to vary the opening 92 between passage 59 or 19 and valve 99 to control the flow of material through the supply openings and into the chamber 69. These adjustable valves 99 may be associated with both of the openings 69 or 19 and are independently operable to vary the flow in either or both of said openings 99 or 19.

Receiving chamber 69 is in axial alignment with valve operating chamber 45 and valve rod 59 projects into said chamber and is slidably movable toward and away from the front end of the chamber 99, is slidably borne and guided in a packing nut 95 screwed to the rear of said chamber 68. The rearwardly extending portion 96 of nut 85 is externally threaded and a hollow clamping nut 91 is screwed thereon and serves to force and cla-mp packing material 98 tightly about the valve rod 59 and seal the rear end of said receiving chamber 69 against leakage while permitting sliding movement of the said rod. The front end of chamber 99 is internally screw-threaded and terminates in the flat front face 99 of the barrel I, and a fluid tip 99 is adapted to be received in said screw threaded chamber 99.

This fluid tip 99 is provided with a screwthreaded extension 9|, whereby it is secured in position engaging the forward screw thread of the receiving chamber 99. It has a hexagonally or polygonally shaped flange 92 directly adjacent the extension 9| anda conical portion having a circular recess or slot 93 to provide a pair of frusta-conical portions 94 and 95, with the greatest diameter of portion 94 being equal to the perpendicular distance betweenthe faces of flange 92. The forward end of tip 99 is a short conical section 99 terminating in a small diameter cylindrical nose. The forward end of conical open- 6 f 'ins llactsasavalveseatforthefreeforward end of valve rod 5l. The nose has a small diameter opening 91 therein communicating with a conical opening 98 in cone 99 which in turn communicates with a cylindrical opening 99 whose diamgter is equal to that of the base of cone openins 9 The flange 92 has a shallow annular recess |99 therein at about the vmidthickness thereof.

Equally spaced small cylindrical openings III' '|92 are of uniform depth and length. -The lower ends of the slots |92 terminate near the ends of the openings I9I.

The plunger or front portion of the valve rod 59 is in the form roughly of an elongated needle or rod having a rear portion |95 extending from the shoulder 53, through opening 5I, packing nut 99 and bushing 95 and into chamber 69, and a front portion |95 of smaller diameter than rear portion |95 and terminating in a conical or valve tip |91. When the valve tip |91 seats in the conical opening 9|?. and is normally in this position when the trigger is not actuated by any outside force, the fluid receiving chamber is sealed to prevent the passage of uid out of the orifice 91. When said valve |91 is opened by pressure on the trigger as before described, fluid passes from the chamber 99 and out through the forward end of the orifice 91 in the nose.

Theair 'passages I9 and 92 extend horizontally along the barrel toward its forward end, to the respective chambers |98 and |99 (Fig. II) and converge slightly in their approach thereto. A passageway lI I9 extends upwardly and outwardly in the barrel II from the chamber |98 and terminates in the flat front face |I2 of said barrel directly adjacent and outside of the flange 92.

A passageway I I3 leads upwardly and outwardly in the barrel I from the chamber I 99 and also terminates in the front flat face I|2 of said barrel ai; a diametrically opposite point to terminus of said passageway I 99. The passageway I I3 communicates with the recess |99. The chambers |99 and |99 are provided to facilitate the boring of the respective passageways II9 and I9 and each is suitably sealed at its lower end by the respective sealing plugs II5 and IIS. In this manner, two continuous air passages from the air distributing chamber I6 to the tip or forward end of the barrel are provided, one of which is independently valve controlled through the valve 33 whereby air through passageways 32, |99 and II3 may be adjustably restricted or cut oif entirely as desired.

A nozzle |29 may be applied over the fluid tip 99 and is preferably of the external or outside mix type. The nozzle |29 is of generally cylindrical external contour and has a lower portion of enlarged diameter to provide a retaining shoulder I2I. 'I'he nozzle |29 has a front closure |22 and is hollow to provide a generally conical internal face |23. The closure |22 has a central circular opening |24 therethrough and the diameter of this opening is somewhat larger than the external diameter of the nose of fluid tip 99. AThe nozzle |29 also includes a pair of air jet outlet members |25 integral with closure |23 and longitudinally extending therefrom. These members |25 are di ametrically arranged at opposite sides of the opening |24.

abattue Theupperpartsofthefacingsides |20ofmembers |20 slant upwardly outwardly away from each other. Each of said members is provided with a e outlet |20 disposed at about right angles to the face |25 and communicating with an opening |20 which extends from opening |20 and extends through the lower or inner face of the nozzle |20. The nozzle |20 is mounted on the iluid tip 00 as shown in Figures I and l1. with the inner edge of the lower part of nozzle |20 abutting against the inner edge oi ilange 32. The lower face of nozzle |20 extends outwardly beyond ange 02 leaving exposed the lower end of passageways |23. The entire outermost conical faces of portions 04 and of fluid tip 9 snugly abut against the lower internal conical face |23. The nose of the fluid tip 00 extends through the opening |24 and its outer extremity is located beyond the front face of closure |22. Between the inner face of closure |22 and the upper end of the conical portion 35 is an air chamber |32. A threaded collar or clamping nut |33 is threadedly connected to the front end of barrel and has a ilange |34 abutting against shoulder |2| to demountably lock the fluid tip 00 in position. The desired angular position of the members |25 may be varied by merely loosening the nut |33 and rotating the nozzle the proper amount.

Air under pressure passes out of passageway I3, into annular recess |00 and then through the equally spaced openings ||I|. From the openings I0|, the air travels throh into annularrecess 03, through the slots |02, into the chamber |32, through the portion of the passage |24 around the circumference of the projecting nose of iluid tip 90.

'I'he air as it passes beyond the front face of the closure |22 sets up an eddy current effect at the discharge terminus of said nose of tip 90. These eddy current eiects serve to atomize and mix the fluid as it passes out of said nose and towards the surface to be coated. Air under pressure from the passageway ||0 enters the chamber |40, whose onerside is formed by the lock nut |33, then vpasses through the passageways |29, then through |28 and project towards each other to further mix and control the shape and dimensions of the spray as it leaves the nozzle |20.

The novel spray gun may be coupled with different sources of coating materials through nexible hose lines |53 and |65 connected to the nipples 'i3 for delivering the coating materials under pressure to the chamber Il. 'I'he spray gun may be coupled with a flexible hose |30 carrying air under pressure and connected thereto at the lower end of the handle |2 to supply air under pressure to the passageway |4.

In operation, after the pressure of the sources of coating material supply has been properly ad- )usted and pressure in the air supply line to the spraying device has been properly adiusted, and the spraying device has been connected to said air `supply line and to the fluid supply lines from said sources of coating material supply, the operator is ready to spray coat. In the practice of this invention. it is preferable to employ paints of different viscosities in the lines |00 and |65 and I prefer that the higher viscosity paint be in line |30 connected to the passageway 60 and both paints be at the same pressure. Paint is conveyed under pressure through hose I, front passageway 'Il from which it discharges as a free column through the passageway 0l and into the chamber Il. Paint is conveyed under pressure through hose III, rear passageway Il from which it discharges as a free column through passageway and into chamber 03. The air under pressure is conveyed through hose |03 to the passageway i3 into chamber Il. With the valve 33 set in the open position shown in Figure II, the spraying device is ready for operation. It is to be understood that if desired the valve 00 may be completely eliminated and is employed only if adjustable means for regulating the ilow of uids in passageways 60 and 10 are desired. The chamber as shown has an internal diameter of about .375 and the diameters of the openings 'I1 may vary preferably between about .025" and .10" and are at least .5" long.

The operator forces the trigger 38 towards the handle i3. The trigger 38 rst strikes the rod 24 to unseat valve 23 whereupon the air passes into chamber I6, through passages I8, I9, |08, |||l into chamber |40 and through passages |29 and |23; and also from chamber I6 through passages 20, chamber 33, passages 32, |09, ||3, slot |00, openings lili, slots 93, |02, chamber |32 and then between the outside of the nose of uid tip 90 and the orifice |24.

While the air continues following the aforementioned path, the trigger strikes the nose 58 and retracts the valve rod 50 to open the fluid or paint discharge orifice 91 at the end of the common paint receiving chamber formed by the aligned chamber 68, and the chamber in said fluid tip 90. The different colored paints discharge out of said orifice 91 and are atomized and mixed by the eddy currents created by the discharge of air through orifice |24 and as the atomized paint mixture in its course of travel towards the surface to be painted passes between the air jets from openings |28, it is further mixed and the configuration of the spray is modified. When the trigger 38 is released, the orifice 91 is first closed by the valve rod 50 and then the valve I5 assumes its closed position.

The foregoing system and spray device may be employed by even an unskilled workman and may be employed to carry out my novel methods for obtaining unique spray coatings of different col ors. Although the invention has been described Vin detail, it is not to be limited thereby because many changes and modifications may be made 50 without departing therefrom.

.What is claimed:

1. A paint or the like spraying device, capable of producing spetter finish coatings in a single spraying operation. comprising a body, an elongated iluid receiving chamber having a restricted discharge oriilce at one end thereof, a plurality of separate iluid supply inlets communicating with said chamber, each of said inlets being com- Y pletely unsurrounded by the other throughout the 60 entire length thereof, the central longitudinal axis of each of said inlets being at an angle to the central .longitudinal axis of said chamber, the distance between said oriilce and the point at which said axis of one of said inlets enters said 65'-I chamber being greater than the distance between said orifice and the point at which said axis of another of said inlets enters said chamber, said body having a passageway for transmitting air under pressure close to and externally of said 70 orii'lce to convert into a spray the iluid discharge therefrom.

2. A paint or the like spraying device, capable of producing spetter finish coatings in a single spraying operation, comprising a body, an elongated i'luid receiving chamber in said body, a dllcharge tip having a discharge orifice at one end thereof and communicating with said chamber, a plurality of separate fluid supply inlets communicating with said chamber, the central longitudinal axis of each of said inlets being at an angle to the central longitudinal axis of said chamber, the distance between said orifice and the point at which said axis of one of said inlets enters said chamber being greater than the distance between said orifice and the point at which said axis of another of said inlets enters said chamber, each of said inlets being completely unsurrounded by the other throughout the entire length thereof, a housing surrounding said tip and connected to said body, said housing having4 a small opening in the front end thereof, the ifice end of said tip extending through said opening, said body having a passageway for transmitting air under pressure and communicating with said opening for the passage of air under pressure out of said opening and close to and externally of said orifice to convert fluid discharge therefrom into a spray.

3. A paint or the like spraying device, capable of producing spatter finish coatings in a single spraying operation, comprising a body, an elongated uid receiving chamber in said body. a discharge tip having a discharge orifice at one end thereof and communicating with said chamber, a plurality of separate fluid supply inlets communicating with said chamber, extending downwardly therefrom and spaced from each other along the length of said chamber, each of said inlets being completely unsurrounded by the other throughout the entire length thereof, a housing surrounding said tip and connected to said body, said housing having a small opening in the front end thereof, the orifice end of said tip extending through said opening, said body having a passageway for transmitting air under pressure and communicating with said opening for the passage of air under pressure out of said opening and close to said orifice to convert iiuid discharge therefrom into a spray.

4. A paint or the like spraying device, capable of producing spatter finish coatings in a single spraying operation, comprising a body, an elm 10 gated fluid receiving chamber in said body, a diacharge tip having a discharge orifice at one end thereof and communicating with said chamber, a plurality of separate fluid supply inlets communicating with said chamber, extending downwardly therefrom and disposed one completely behind the other along the length of said chamber, a housing surrounding said tip and connected to said body, said housing having a small opening in the front end thereof, the orifice end of said tip extending through said opening, said body having a passageway for transmitting air under pressure, and communicating with said opening for the passage of air under pressure out of said opening and close to said orifice to convert uid discharge therefrom into a spray, said housing having air passageways for directing air jets towards each other to modify the shape of said spray. i

AUSTIN H. DOWNS.

REFERENCES CITED The following references are of record in the file of this ipatent:

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